#身体质量指数BMI
y_or_n=input('是否退出程序(y/n)?：')
while y_or_n != 'y'
    height,weight = eval(input("请输入身高（米），体重（公斤）【用逗号隔开】:"))
    bmi = weight/pow(height,2)
    print("BMI数值为：{:.2f}".format(bmi))
    who,nat="",""
    if bmi < 18.5:
        who, nat = "偏瘦", "偏瘦"
    elif 18.5 <= bmi < 24: 
        who, nat = "正常", "正常"
    elif 24 <= bmi < 25:
        who, nat = "正常", "偏胖"
    elif 25 <= bmi < 28:
        who, nat = "偏胖", "偏胖"
    elif 28 <= bmi < 30:
        who, nat = "偏胖", "肥胖"
    else:
        who, nat = "肥胖", "肥胖"
print("BMI 指标为:国际'{0}', 国内'{1}'".format(who,nat))
y_or_n=input('是否退出程序（y/n）?:')




